1. Field of the Invention
The present invention relates to an electrical adapter, and more particularly relates to a generator hub adapter that is used with a bicycle generator hub, the bicycle generator hub including a hub axle, a stator portion of a generator mounted on the hub axle, a connector that is also held by a nut member to the hub axle, the connector being provided with a first contact terminal that is electrically connected to the stator portion of the generator, with the electrical adaptor also being supported on the hub axle and being electrically connected to a rotor portion of the generator.
2. Background Information
Bicycle generator hubs are well known. In such bicycle generator hubs, a stator portion of a generator is mounted within a hub located at the center of one of the bicycle wheels. The bicycle generator hub includes a hub axle, a stator portion of the generator and a connector. The stator portion of the generator is typically fixed or non-rotatably mounted to the hub axle. The stator portion is further electrically connected to a contact within the connector. The connector is preferably fixed by a nut member to the hub axle. The connector is typically an insulated member that includes the contact to allow for easy attachment of power supply wires from electrical devices such as a headlamp installed on a bicycle. In the past, the connector was mounted to the hub axle alongside the stator of the generator, and electrical wiring for connecting to the electrical device was connected to the contact of the connector (for example, see Japanese Laid-Open Patent Application 2004-299418). These connectors are known to come in a one-wire configuration having just a first contact terminal electrically connected via internal wiring to the stator of the generator. A rotor of the generator is typically grounded to the frame of the bicycle. Therefore, the frame of the bicycle served as a portion of the generator wiring to complete the circuit for powering devices mounted on the bicycle.
A two-wire connector configuration having a first contact terminal electrically connected via internal wiring to one component of the generator, and a second contact terminal electrically connected via the hub axle to the other component of the generator is also known. In a two-wire connector configuration, the first contact terminal is generally the same as the one-wire configuration. The second contact terminal is achieved by attaching a second connector to the frame or hub axel, which is in electrical contact with the rotor of the generator.
A one-wire type of connector makes wiring work easier because only one wire is needed to power the electrical device with the frame providing a ground. Accordingly, this design is widely employed for ordinary bicycles used for commuting to work or school, running errands, and so forth. However, two-wire connector having two (first and second) contact terminals is becoming widely desired in some markets because newer frames may not easily provide electrical conductivity. For example, some frames are provided with thick paint finishes that must be scratched down to metal in order to electrical contact. Further, some frames are made of composite materials which are non-conductive. Bicycles using such frames being equipped with electrical devices other than headlamps, such power assisted shifting mechanisms that require electrical power.
The cost of producing two different designed hub generators, a one wire type and a two wire type, complicates manufacturing and makes each of the two types more expensive.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved hub generator that is easily modified to change it to and from a one wire type to a two wire-type. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.